This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 0 |
| 3 | -90 |
| 4 | 117 |
| 5 | 0 |
| 6 | -216 |
| 7 | 450 |
| 8 | 0 |
| 9 | -738 |
| 10 | 648 |
| 11 | 0 |
| 12 | -1170 |
| 13 | 1530 |
| 14 | 0 |
| 15 | -1728 |
| 16 | 1845 |
| 17 | 0 |
| 18 | -2160 |
| 19 | 3258 |
| 20 | 0 |
| 21 | -4500 |
| 22 | 3240 |
| 23 | 0 |
| 24 | -3672 |
| 25 | 5409 |
| 26 | 0 |
| 27 | -6570 |
| 28 | 5850 |
| 29 | 0 |
| 30 | -6480 |
| 31 | 8658 |
| 32 | 0 |
| 33 | -8640 |
| 34 | 7776 |
| 35 | 0 |
| 36 | -9594 |
| 37 | 12330 |
| 38 | 0 |
| 39 | -15300 |
| 40 | 11016 |
| 41 | 0 |
| 42 | -10800 |
| 43 | 16650 |
| 44 | 0 |
| 45 | -17280 |
| 46 | 14256 |
| 47 | 0 |
| 48 | -18450 |